Awk/Perl convert textfile to csv with sensible format - linux

Question

I have a historical autogenerated logfile with the following format that I would like to convert to a csv file prior to uploading to a database
--------------------------------------
Thu Jul 8 09:34:12 BST 2010
BLUE Head 1
Duration = 20 s
Activity = 14.9 MBq
Sensitivity = 312 cps/MBq
--------------------------------------
Thu Jul 8 09:34:55 BST 2010
BLUE Head 1
Duration = 20 s
Activity = 14.9 MBq
Sensitivity = 318 cps/MBq
--------------------------------------
Thu Jul 8 10:13:39 BST 2010
RED Head 1
Duration = 20 s
Activity = 14.9 MBq
Sensitivity = 307 cps/MBq
--------------------------------------
Thu Jul 8 10:14:10 BST 2010
RED Head 1
Duration = 20 s
Activity = 14.9 MBq
Sensitivity = 305 cps/MBq
--------------------------------------
Mon Jul 19 10:11:18 BST 2010
BLUE Head 1
Duration = 20 s
Activity = 12.4 MBq
Sensitivity = 326 cps/MBq
--------------------------------------
Mon Jul 19 10:12:09 BST 2010
BLUE Head 1
Duration = 20 s
Activity = 12.4 MBq
Sensitivity = 333 cps/MBq
--------------------------------------
Mon Jul 19 10:13:57 BST 2010
RED Head 1
Duration = 20 s
Activity = 12.4 MBq
Sensitivity = 338 cps/MBq
--------------------------------------
Mon Jul 19 10:14:45 BST 2010
RED Head 1
Duration = 20 s
Activity = 12.4 MBq
Sensitivity = 340 cps/MBq
--------------------------------------
I would like to convert the logfile to the following format
Date,Camera,Head,Duration,Activity
08/07/10,BLUE,1,20,14.9
08/07/10,BLUE,1,20,14.9
08/07/10,RED,1,20,14.9
08/07/10,RED,1,20,14.9
I have used awk to get me close to what I wish
awk 'BEGIN {print "Date,Camera,Head,Duration,Activity";RS = "--------------------------------------"; FS="\n";}; {OFS=",";split($3, a, " ");split($4,b, " "); split($5,c," ");print $2,a[1],a[3],b[3],c[3]}' sensitivity.txt > sensitivity.csv
which gives me
Date,Camera,Head,Duration,Activity
,,,,
Thu Jul 8 09:34:12 BST 2010,BLUE,1,20,14.9
Thu Jul 8 09:34:55 BST 2010,BLUE,1,20,14.9
Thu Jul 8 10:13:39 BST 2010,RED,1,20,14.9
Thu Jul 8 10:14:10 BST 2010,RED,1,20,14.9
How can I
(a) get rid of the 4 output field separators in line 4
(b) Convert the date format from Thu Jul 8 09:34:12 BST 2010 to DD/MM/YY (Can I do this in pure awk or by piping to perl)

Answer 1

#sudo_O's answer is fine but here's an alternative:
$ cat tst.awk
BEGIN{ RS="---+\n"; OFS=","; months="JanFebMarAprMayJunJulAugSepOctNovDec" }
NR==1{ print "Date","Camera","Head","Duration","Activity"; next }
{ print sprintf("%04d%02d%02d",$6,(match(months,$2)+2)/3,$3),$7,$9,$12,$16 }
$ gawk -f tst.awk file
Date,Camera,Head,Duration,Activity
20100708,BLUE,1,20,14.9
20100708,BLUE,1,20,14.9
20100708,RED,1,20,14.9
20100708,RED,1,20,14.9
20100719,BLUE,1,20,12.4
20100719,BLUE,1,20,12.4
20100719,RED,1,20,12.4
20100719,RED,1,20,12.4
Note that I used GNU awk above so I could set the RS to more than a single character. With other awks just convert all the "---..."s lines to a blank line or control character or something and set RS accordingly before running the script.
If you don't like my suggested date format, tweak the sprintf() to suit.

Answer 2

This straight forward awk script will do the job:
BEGIN {
n=split("Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec",month,"|")
for (i=1;i<=n;i++) {
month_index[month[i]] = i
}
print "Date,Camera,Head,Duration,Activity"
}
/^-*$/{
i=0
next
}
{
i++
}
i==1{
printf "%02d/%02d/%02d,",$3,month_index[$2],substr($6,3)
}
i==2{
printf "%s,%d,",$1,$3
}
i==3{
printf "%d,",$3
}
i==4{
printf "%.1f\n",$3
}
Outputs:
$ awk -f script.awk file
08/07/10,BLUE,1,20,14.9
08/07/10,BLUE,1,20,14.9
08/07/10,RED,1,20,14.9
08/07/10,RED,1,20,14.9
19/07/10,BLUE,1,20,12.4
19/07/10,BLUE,1,20,12.4
19/07/10,RED,1,20,12.4
19/07/10,RED,1,20,12.4

Answer 3

I figured I would show how to actually parse the input, rather than just performing string transformations.
#! /usr/bin/env perl
use strict;
use warnings;
use Date::Parse;
use Date::Format;
use Text::CSV;
sub convert_date{
my $time = str2time($_[0]);
# iso 8601 style:
return time2str('%Y-%m-%d',$time); # YYYY-MM-DD
# or the outdated style output you wanted
return time2str('%d/%m/%y',$time); # DD/MM/YY
}
my %multiply_table = (
s => 1,
m => 60,
h => 60 * 60,
d => 60 * 60 * 24,
);
sub convert_duration{
my($d,$s) = $_[0] =~ /^ \s* (\d+) \s* (\w) \s* $/x;
die "Invalid duration '$_[0]'" unless $d && $s;
return $d * $multiply_table{$s};
}
my #field_list = qw'Date Camera Head Duration Activity';
my $csv = Text::CSV->new( { eol => "\n" } );
# print header
$csv->print( \*STDOUT, \#field_list );
# set record separator
local $/ = ('-' x 38) . "\n";
# parse data
while(<>){
chomp; # remove record separator
next unless $_; # skip empty section
my($time,$camdat,#fields) = split m/\n/; # split up the fields
my %data;
# split camera and head fields
#data{qw(Camera Head)} = split /\s+Head\s+/, $camdat;
# parse lines like:
# Duration = 20 s
# Activity = 14.9 MBq
# Sensitivity = 305 cps/MBq
for(#fields){
my($key,$value) = /(\w+) \s* = \s* (.*) /x;
$data{$key} = $value;
}
# at this point we start reducing precision
$data{Date} = convert_date( $time );
# remove measurement units
$data{Duration} = convert_duration($data{Duration}); # safe
$data{Activity} =~ s/[^\d]*$//; # unsafe
$csv->print(\*STDOUT, [#data{#field_list}]);
}